Laser images are widely used in the medical imaging field to produce visual representations on film of digital medical images. Laser imagers typically include a film supply system, a film exposure system, a film processing system, and a transport system that moves film from the film supply through the laser imager along a transport path. The film supply system generally comprises a supply of unexposed film stacked in a cartridge or magazine. The transport system typically includes a mechanism for removing individual sheets of film from the cartridge, and a feeder system for delivering the individual sheets of film to the transport path along which the film is transported through the film exposure and processing systems to an output tray for access by a user.
When transferring the individual sheets of film to the transport path, it is important that the film be properly delivered to the transport path. A piece of film that is delivered at an angle, or skewed, relative to the direction of travel along the transport path can cause an image to be improperly produced on the film and cause film jams along the transport path.
One type of feeder system includes a drive roller and an idler roller that together form a feed roller pair for receiving an individual sheet of film after its removal from the film supply. Initially, the idler roller is held out of contact with the drive roller. Upon a sheet of film being placed in contact with the drive roller, a gear drive system, which is coupled to each end of the idler roller with a pair of spring-loaded links, drives the idler roller to a closed position to secure the film between the idler roller and the drive roller. The drive roller is then driven to transport the film away from the film supply to the transport path.
In the closed position, the spring-loaded links are designed to provide closing pressure between the two rollers. However, since the gear drive system is directly coupled to the idler roller via the spring loaded links, the gear drive system continues to influence the closing pressure between the idler roller and drive roller when in the closed position. During assembly, the gear drive system can be improperly installed, resulting in an uneven closing of the idler roller against the drive roller. In such an instance, the closing pressure can vary between the ends of the rollers, resulting in the film becoming skewed as it is delivered from the film supply to the transport path.
Thus, there is a need for an improved feeder system for delivering film from a film supply to a transport path in an imaging apparatus.